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931.
In this paper,kinematic formulae in a real space form are investigated.A kinematic formula for homogeneous polynomial of degree 4 on the second fundamental forms in a real space form is obtained.The formula obtained is a concrete form of the result of Howard and the analogue of the known formula of Chen and Zhou. 相似文献
932.
In this paper,we consider the existence of a uniform exponential attractor for the nonautonomous partly dissipative lattice dynamical system with quasiperiodic external forces. 相似文献
933.
用 R T P C R技术从 C S F V H C L V 株 F482 代感染兔脾的细胞总 R N A 中分段扩增出了 C S F V E2 基因特异的3 个部分重叠的 D N A 片段(大小分别为 499 bp、572 bp 和 245 bp),并将之分别克隆到p G E M T 载体上 经核苷酸序列测定和片段重叠完成了包含 E2 全长基因的 1 144 bp 序列的测定,其 G C含量为49.0% :核苷酸序列与国外报道的各株病毒的 E2 基因同源性分别为83.5% ~97.5% ;其推导的氨基酸序列的同源性也分别为89.3%~96.2% ,变异主要分布在 E2 蛋白的 N 半部分 相似文献
934.
This paper is devoted to constructing an authentication code with arbitration using subspaces of vector spaces over finite fields.Moreover,if we choose the encoding rules of the transmitter and the decoding rules of the receiver according to a uniform probability distribution,then some parameters and the probabilities of successful attacks are computed. 相似文献
935.
This paper constructs a class of Harish-Chandra modules with multiplicity ≤1 of the two parameter deformation of Virasoro algebra and proves a classification theorem. 相似文献
936.
937.
938.
Chang‐xi Wang Jia‐li Li Xue‐ding Wang Long‐shan Liu Xiao Chen Min Huang 《Biomedical chromatography : BMC》2010,24(4):399-405
A liquid chromatography/tandem mass spectrometry (LC‐MS/MS) method was developed and validated for determining tacrolimus (FK506) in rat tissues to study the effect of Schisandra sphenanthera extract on FK506 tissue distribution. After a liquid–liquid extraction with ethyl acetate, FK506 and ascomycin (IS) were subjected to LC‐MS/MS analysis using positive electrospray ionization under multiple reactions monitoring mode. Chromatographic separation of FK506 and ascomycin was achieved on a Hypersil BDS C18 column with a mobile phase consisting of methanol‐water (containing 2 mM ammonium acetate, 95 : 5, v/v). The intra‐ and inter‐batch precision of the method were less than 8.8 and 9.8%, respectively. The intra‐ and inter‐batch accuracies ranged from 97.5 to 104.0%. The lowest limit of quantification for FK506 was 0.5 ng/mL. The method was applied to a FK506 tissue distribution study with or without a dose of Wuzhi (WZ) tablet. Most of the FK506 tissue concentrations were slightly increased after a concomitant WZ tablet dose, but the whole blood concentration of FK506 was dramatically increased 3‐fold after a concomitant WZ tablet dose. These results indicated that the LC‐MS/MS method was rapid and sensitive enough to quantify FK506 in different rat tissues, and strict drug monitoring is recommended when co‐administering WZ tablet in clinical use. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
939.
940.
A micrometer-sized nanostructured, magnetic, ball-like Fe x O y -CeO2 composite was synthesized through an ethylene-glycol mediated process. The synthesized samples were characterized by scanning electron microscopy combined with energydisperse X-ray analysis, transmission electron microscopy and X-ray powder diffraction. In the synthesis system, polyethylene glycol (PEG) and urea were found to play significant roles in the formation of the micrometer-sized spherical architecture of the precursor. The details of morphology and particle size could be changed with the initial concentration of Fe(NO3)3·9H2O and Ce(NO3)3·6H2O as the reactants. The magnetic Fe x O y -CeO2 composite with a similar morphology was readily obtained by calcination from the precursor. The characterization of transmission electron microscopy showed the calcined ball-like architecture was a highly porous structure consisting of many nanoparticles. Because of the micrometer-sized nanostructure and the multi-components as well as the magnetism, the as-obtained Fe x O y -CeO2 composite showed better activity and potentially easy recovery for the harmless degradation of hexachlorobenzene (HCB). 相似文献